Mutang and antimutagnic activities of extract from white kwao krua Pureraria mirifica, red kwao krua Burea superba and black kwao krua Mucuna colletti by ames test

Cytotoxicity evaluation of the 3 plant extracts on Salmonella Typhimurium TA98 and TA 100 revealed that Mucuna collettii extract exhibited the strongest cytotoxicity on S. Typhimurium TA98. Mutagenic and antimutagenic activities of Pueraria mirifica, Butea superba and Mucuna collettii collected from 28, 24 and 4 provinces, respectively were tested. Their extracts were evaluated by Ames test using S. Typhimurium strain TA98 and TA100 under the absence and presence of metabolic activity conditions at the concentration of 0.625, 1.25 and 2.5 mg/plate (100 µl) in comparison with the control. No mutagenicity was induced by all plant extracts except B. superba collected from Ratchaburi province which exhibited mutagenicity (P < 0.05) in S. Typhimurium strain TA98 under the absence of metabolic activity condition at the concentration of 2.5 mg/plate (100 µl). In the test with mutagenicity on Salmonella strains, all plant extracts exhibited significant inhibition (P<0.05) against 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2) and Benzo(a)Pyrene (B(a)P). P. mirifica collected from Uthai Thani, B. superba collected from Kanchanaburi, M. collettii collected from Chiang Mai inhibited mutagenicity induced by AF-2 0.01 µg/plate (100 µl) on S. Typhimurium strain TA100 at the inhibition percentage of 25.72, 53.36 and 50.55, respectively. P. mirifica collected from Sukhothai, B. superba collected from Chonburi, M. collettii collected from Kanchanaburi inhibited mutagenicity induced by B(a)P 5 µg/plate on S. Typhimurium strain TA100 at the inhibition percentage of 55.95, 88.61 and 92.87, respectively. The mutagenicity and antimutagenicity assay of the plant extracts were confirmed in rec assay with Bacillus subtilis strain H17 and H45 under the absence of metabolic activity conditions. All plant extracts at the concentration of 2.5, 5 and 10 mg/well (10 µl) exhibited no mutagenicity. Mucuna collettii collected from Chiang Rai and Butea superba collected from Loci exhibited significant inhibition (P < 0.05) against AF-2 0.1 µg/well (10 µl) at the concentration of 2.50 mg/well (10 µl), and P. mirifica collected from Uthai Thani exhibited significant inhibition (P < 0.05) against AF-2 at the concentration of 10 mg/well (10 µl). In summary, all Kwao Krua in this study showed no mutagenicity but antimutagenicity was detected in certain samples. The strongest antimutagenicity was found in M. collettii.